Works quickly to reduce chlorine and bromine levels in case of an accidental overdose, resulting in water that's unsafe to swim. No more waiting for hours or days until sanitizer levels are back within a safe range. Simply test the free available chlorine or bromine levels in the water, determine the appropriate dosage of Chlorine Neutralizer needed, and circulate the product for about 30 minutes. Retest the sanitizer levels before entering the water, and add a follow-up dose if needed.